HydroxyPropyyl Metylcellulose (HPMC) yog ib feem siv dej-soluble cellulose dav siv nyob rau hauv ncua kev ncua. Qhov kev kawm tsis ruaj khov yog hais txog lub peev xwm ntawm cov khoom muaj peev xwm los nyob twj ywm uniformly dispersed nyob rau hauv ib lub sij hawm ua kua rau lub sijhawm ntev los yam tsis muaj qhov tseem ceeb sedimentation lossis kev sib sau ua ke. Lub cev muaj zog thiab tshuaj lom neeg ntawm HPMC ua rau nws ua lub luag haujlwm tseem ceeb hauv kev txhim kho qhov ruaj khov ntawm kev ncua.
Cov Khoom Yooj Yim ntawm HPMC
Lub cev thiab tshuaj
HPMC yog qhov kev txiav txim siab tau los ntawm kev methylation ib nrab me thiab hydroxypropation ntawm cellulose. Nws cov qauv molecular muaj hydrophilic hydroxyl (-oh) thiab hydrophobic mexyoxy (-hiv) thiab hydublepropyl, uas ua rau nws dej-soluble thiab doluble thiab nto-zog. HPMC tuaj yeem tsim cov tshuaj tua kab hauv dej, thiab nws cov viscosity hloov nrog ntau ntau, kub thiab ph.
Viscosity Khoom
Kev daws teeb meem ntawm HPMC cov khoom pov thawj cov khoom ntawm cov kua tsis yog-Newtonian, thiab nws viscosity txo qis, nws ua haujlwm shear-thinning cov khoom. Cov cuab yeej no muaj qhov tseem ceeb uas cuam tshuam rau kev ncua kev coj tus cwj pwm uas nws tuaj yeem muab cov viscosts tsim nyog kom tabkaub thaum tsis txhob muaj ntau dhau thaum ua kom nplawm.
Mechanism ntawm cov cawv ntawm HPMC ntawm kev ruaj ntseg ntawm kev ncua
1. Thickening nyhuv
Cov nyhuv thickening ntawm HPMC yog txhawm rau txhawm rau txhawm rau txhaws ntawm cov khoom ntawm cov viscosity ntawm kev ncua. Cov nyhuv thickening yog feem ntau tau cuam tshuam hauv cov hauv qab no:
Ua kom muaj viscosity ntawm nruab nrab: HPMC tuaj yeem ua kom qhov kev ncua ntawm viscosity, yog li txo cov sedimentation tus nqi ntawm cov khoom hauv cov kua. Qhov no yog vim tias raws li stokes 'txoj cai lij choj, tus nqi sedimentation tus nqi yog inversely proortional rau viscosity ntawm nruab nrab. Qhov nce hauv viscosity tuaj yeem ua kom qeeb qeeb ntawm cov sedimentation qeeb ntawm cov lus thiab txhim kho kev ruaj ntseg ntawm kev ncua.
Tsim ib tug qauv sib tw ntawm cov qauv siv hluav taws xob Cov qauv network no tau tswj hwm los ntawm hydrogen bonds thiab hydrophobic sib txuas lus, ua kom cov khoom tawg tsis sib xws.
2. Electrostatic effect
Cov qauv molecular ntawm HPMC nqa qee tus nqi (piv txwv li, los ntawm hydroxyl lossis hydroxypropyl pawg nyob rau hauv kev ncua. Los kho cov nplaim dej muaj peev xwm ntawm cov hais, HPMC tuaj yeem nce electrostatic repulsion ntawm kev sib sau ua ke thiab flocculation ntawm hais.
Cov nyhuv tsub nqi: Tus nqi HPMC tuaj yeem hloov cov nqi hluav taws xob qis ntawm cov khoom siv hluav taws xob, thiab cov khoom lag luam qeeb rau kev sib sau ua ke.
Cov tshuab colloidal: hauv qee cov tshuab colloidal, HPMC tuaj yeem pab cuam tshuam nrog cuam tshuam rau lawv los ntawm aggregating vim yog van der wa der warces lossis lwm cov rog zoo nkauj.
3.. Cov nyhuv cuam tshuam
HPMC Molecules tuaj yeem tsim lub spatial teeb meem txheej txheem hauv kev raug tshem tawm, uas tuaj yeem tiv thaiv kev tiv tauj thiab kev sib thab, yog li nce qhov ruaj khov ntawm kev ncua.
Spatial Barrier: HPMC Molecules tsim ib qho kev ua rau cov khoom ua si hauv cov khoom noj, yog li txo qhov kev sib cav sib ceg thiab kev ua kom tiav.
Qhov chaw ruaj khov: vim muaj HPMC lwg me me, thiab lub cev lub cev no txo qis cov lus ncua kom muaj kev sib cais rau lub sijhawm ntev dua.
4. Cov kev ua si saum npoo
Cov kev ua si saum npoo HPMC tso cai rau nws adsorb nyob rau saum npoo ntawm cov khoom khov kho kom ua cov txheej ruaj khov. Cov txheej no tsis tsuas yog tso cov nplaim hluavtaws, tab sis kuj ua rau cov khoom siv hydrophilicity ntawm cov khoom siv, ua kom yooj yim rau kev tawg hauv cov xov xwm ua kua.
Kev Hloov Kho Nto: los ntawm Adsorbing ntawm cov kab npoo av, HPMC tuaj yeem hloov pauv lub cev thiab tshuaj lom neeg ntawm qhov sib luag thiab kev ua kom muaj zog thiab ruaj khov ntawm cov lus.
Txo cov nrees cuam tshuam cov nrees: Cov kev ua si saum npoo ntawm HPMC tuaj yeem txo cov nro hauv nruab nrab ntawm cov kua nruab nrab ntawm cov khoom siv ua kua thiab qhov sib luag, ua kom yooj yim rau covyees dispersed hauv nruab nrab.
Piv txwv ntawm HPMC cov ntawv thov nyob rau sib txawv
Kev Raug Tshuaj
Hauv kev raug rho tawm, HPMC feem ntau siv los tswj cov kev sib cais ntawm lub xeev ntawm cov khoom xyaw ua haujlwm. Los ntawm kev kho cov kev xav thiab cov roj ntsha hnyav ntawm HPMC, cov khoom xyaw ua ke tuaj yeem tswj tau tusyees fortibuted thaum lub sij hawm cia thiab siv, ua kom haum xeeb ntawm kev ua tau zoo.
Hauv kev ncua ntawm lub sijhawm ntawm qee cov tshuaj tua kab mob lossis tshuaj tua kab mob, HPMC yog siv los tiv thaiv kev ua yeeb yaj kiab thaum muab cov saj uas tsim nyog thiab fluenty.
Cov tshuaj tua kab
Hauv kev noj tshuaj tua kab, HPMC tuaj yeem txhim kho qhov tsis sib xws ntawm cov tshuaj tua kab hauv dej thiab txo cov kev tso nyiaj ntawm cov tshuaj tua kab, yog li kev txhim kho cov txiaj ntsig thiab kev siv tshuaj tua kab.
Hauv cov tshuaj tua kab noj qabed lossis tshuaj tua lawv tus kheej, HPMC tuaj yeem siv los ua cov khoom xyaw ntawm cov tshuaj tua kab tuaj yeem yog cov khoom siv tshuaj tiv thaiv tusyees thiab txhim kho cov qoob loo tiv thaiv.
Kev Ncua Khoom Noj thiab Kev Ncua Pleev
Hauv kev lag luam thiab kev lag luam kom hniav zoo nkauj, HPMC tau dav siv raws li lub stabilizer thiab thickener. Piv txwv li, hauv cov khoom lag luam xws li emulsions lossis cream, HPMC tuaj yeem txhim kho kev ntxhib los mos ntawm cov khoom lag luam thiab tiv thaiv nag lossis daus.
Hauv cov duab ua paug, HPMC tuaj yeem siv los ua cov ntaub ntawv zoo los muab cov khoom xyaw zoo thiab txhim kho cov khoom xyaw acsly yog cov nyhuv muaj zog ntawm cov khoom tau hloov kho.
HPMC cuam tshuam qhov muaj qhov ruaj khov los ntawm ntau yam kev kawm, txhim kho cov kev cuam tshuam ntau ntxiv, muab cov khoom sib txuam ua kom muaj zog, muab cov qauv sib txuas ntawm cov khoom sib tsoo thiab cov haujlwm saum npoo. Cov txheej txheem no ua haujlwm ua ke ua HPMC cov cuab yeej siv tau zoo rau kev txhim kho qhov ruaj khov ntawm kev ncua. Nws cov ntawv thov thoob plaws hauv cov qauv tshuaj, tshuaj tua kab, khoom noj thiab cov tshuaj pleev cov khoom noj thiab cov tshuaj pleev ib ce ntxiv kom paub meej tias nws cov txiaj ntsig tseem ceeb los ntawm kev ncua kev tshem tawm. Nyob rau yav tom ntej, raws li qhov kev thov rau kev siv ncua ntawv txuas ntxiv ntxiv, kev tshawb fawb thiab kev thov ntawm HPMC yuav txuas ntxiv.
Lub Sijhawm Post: Feb-17-2025